Flavio Roberto Chaves da Silva

Dr. Flavio Roberto Chaves da Silva

orcid

Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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4 August 2024 in Animals
Verified
Journal Article
Open access
PDF file
PGPaulo Henrique Gilio Gasparotto
Paulo Henrique Gilio Gasparotto
ISIgor Santos
Igor Santos
JDJerônimo Vieira Dantas-Filho
Jerônimo Vieira Dantas-Filho
Mariana Soares da SilvaMariana Soares da Silva
Mariana Soares da Silva
FSFernanda dos Anjos Souza
Fernanda dos Anjos Souza
CDCíntia Daudt
Cíntia Daudt
The Bos Taurus Papillomavirus, commonly known as bovine papillomavirus (BPV), can cause lesions in the mucosa of the gastrointestinal tract (GIT) in cattle and induce the formation of papillomas in organs such as the pharynx, esophagus, rumen and reticulum. GIT papillomas can lead to feeding and breathing distress. Moreover, the sample collection is challenging, which reduces the BPV diagnosis in these organs. BPV can cause exophytic nodular, cauliflower-like, flat, filiform or atypical-shape papillomas at the epidermis. Histologically, the papillomas demonstrate orthokeratotic/parakeratotic hyperkeratosis and koilocytosis and, currently, BPV comprises 45 described types. The aim of this study was to carry out the genetic characterization of BPV present in rumen neoplastic lesions of cattle raised extensively in the Western Amazon region, Brazil. A total of 100 papillomatous ruminal samples were collected from animals slaughtered in Ji-Paraná and Urupá municipalities from the Rondônia state, Brazil. The samples were submitted to PCR using the primer pair FAP59/FAP64 and sequenced by the Sanger method. Histopathological analysis was performed on 24 samples, which had enough material for this purpose. As a result, samples were histologically classified as fibropapilloma and squamous papilloma. Among the samples analyzed, it was possible to identify the BPVs 2, 13 (Delta PVs) and 44, with one sample classified as a putative new subtype of BPV44. The present study could identify BPV13 and 44 types in cattle rumen tissues from the Brazilian Amazon region for the first time.

16 May 2025 in Viruses
Verified
Journal Article
Open access
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FSFernanda dos Anjos Souza
Fernanda dos Anjos Souza
CDCíntia Daudt
Cíntia Daudt
ALANDRE DE MEDEIROS COSTA LINS
ANDRE DE MEDEIROS COSTA LINS
ISIgor Santos
Igor Santos
LTLorena Cáceres Tomaya
Lorena Cáceres Tomaya
FSFlavio Roberto Chaves da Silva
Flavio Roberto Chaves da Silva
Bovine papillomaviruses (BPVs) have been widely characterized from cutaneous warts in cattle worldwide. However, there are still limited studies addressing the geographic distribution of viral types and their potential associations with the histopathological characteristics of lesions, particularly in the vast and ecologically diverse Amazon region. This study aimed to histologically and phylogenetically characterize cutaneous papillomatous lesions in cattle from the Vale do Guaporé, located in the Brazilian Western Amazon. A total of 54 wart samples were collected from 44 cattle clinically diagnosed with cutaneous papillomatosis. Histopathological analysis classified 58.33% of cases as fibropapillomas and 39.58% as squamous papillomas. Molecular analysis, based on L1 gene amplification and sequencing, identified the presence of previously reported BPV types (BPV2, 4, 5, 12, 13, and 15), along with a novel BPV14 subtype and three putative new types (PNT). Statistical analysis revealed that BPV2 was significantly associated with fibropapillomas (p = 0.023), whereas BPV13 was linked to cauliflower-like morphological lesions (p = 0.008). These findings enhance the understanding of BPV diversity circulating in cattle from the Amazon region and provide valuable insights into the clinicopathological aspects of bovine cutaneous papillomatosis, which may aid in future epidemiological surveillance and disease control strategies.

2 August 2025 in Microorganisms
Verified
Journal Article
Open access
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JSJeneffer Caroline de Macêdo Sousa
Jeneffer Caroline de Macêdo Sousa
ALANDRE DE MEDEIROS COSTA LINS
ANDRE DE MEDEIROS COSTA LINS
FSFernanda dos Anjos Souza
Fernanda dos Anjos Souza
HMHigor Ortiz Manoel
Higor Ortiz Manoel
Cleyton SIlva de AraújoCleyton SIlva de Araújo
Cleyton SIlva de Araújo
CDCíntia Daudt
Cíntia Daudt
Papillomaviruses (PVs) are double-stranded DNA viruses known to induce a variety of epithelial lesions in dogs, ranging from benign hyperplasia to malignancies. In regions of rich biodiversity such as the Western Amazon, data on the circulation and genetic composition of canine papillomaviruses (CPVs) remain scarce. This study investigated CPV types present in oral and cutaneous papillomatous lesions in domiciled dogs from Acre and Rondônia States, Brazil. Sixty-one dogs with macroscopically consistent lesions were clinically evaluated, and tissue samples were collected for histopathological examination and PCR targeting the L1 gene. Among these, 37% were histologically diagnosed as squamous papillomas or fibropapillomas, and 49.2% (30/61) tested positive for papillomavirus DNA. Sequencing of the L1 gene revealed that most positive samples belonged to CPV1 (Lambdapapillomavirus 2), while one case was identified as CPV8 (Chipapillomavirus 3). Complete genomes of three CPV1 strains were obtained via high-throughput sequencing and showed high identity with CPV1 strains from other Brazilian regions. Phylogenetic analysis confirmed close genetic relationships among isolates across distinct geographic areas. These findings demonstrate the circulation of genetically conserved CPVs in the Amazon and reinforce the value of molecular and histopathological approaches for the accurate diagnosis and surveillance of viral diseases in domestic dogs, especially in ecologically complex regions.

30 June 2020 in Acta Veterinaria Brasilica
Verified
Journal Article
Closed access
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PGPaulo Henrique Gilio Gasparotto
Paulo Henrique Gilio Gasparotto
CSCarlos Alexandre Fernandes dos Santos
Carlos Alexandre Fernandes dos Santos
JDJerônimo Vieira Dantas-Filho
Jerônimo Vieira Dantas-Filho
RFRauane Cristine Santos Ferraz
Rauane Cristine Santos Ferraz
FSFlavio Roberto Chaves da Silva
Flavio Roberto Chaves da Silva
CDCíntia Daudt
Cíntia Daudt
Rhipicephalus microplus is one of the main ectoparasites of dairy cattle in Brazil, whose control is mainly based on the use of chemicals. However, the low variety of chemicals available, coupled with the indiscriminate use of these substances, has led to increased resistance for this tick. The objective of this study was to evaluate the resistance profile of the tick Rhipicephalus microplus to different acaricidal products used on dairy cows in Teixeirópolis-RO, using the Adult Immersion Test (TIA) or biocarrapaticidogram. Data was collected from nine farms by performing nine in vitro evaluation tests on engorged R. microplus females, using six different tick repelling treatments available on the market. Replicates of each treatment with 20 teleogins were performed for each treatment and a control group in distilled water was used for positive and negative controls. The efficiency amplitudes of each group and the average effectiveness of the acaricidal compounds were evaluated and compared by the Kruskal-Wallis test with a significance level of 95%. Statistical analyses were performed in the Action Stat statistical program. The tick repellents tested presented the following effectiveness averages: 100% (Chlorpyrifos at 50% + Cypermethrin at 6%); 99.99% (15% Cypermethrin + Chlorpyrifos at 25% + Citronellal at 1%); 77.63% (Cypermethrin at 20% + Chlorpyrifos at 50%); 100% (15% Cypermethrin + Chlorpyrifos at 25% + Piperonyl butoxide at 1%) -; 21.68% (Amitraz to 12.5%) -; 42.17% (Deltamethrin at 5%). Products with combinations of active ingredients were the most effective, and thus considered the best alternative for tick control.

Verified
Journal Article
Open access
PDF file
Felipe Masiero SalvaraniFelipe Masiero Salvarani
Felipe Masiero Salvarani
KCKaroline Petrini Pinheiro da Cruz
Karoline Petrini Pinheiro da Cruz
FSFlavio Roberto Chaves da Silva
Flavio Roberto Chaves da Silva
CDCíntia Daudt
Cíntia Daudt
Lagochilascariasis is a neglected zoonotic helminthiasis, caused by Lagochilascaris minor, characterized by a complex and not well understood transmission cycle. This parasitic disease is endemic to Latin America, particularly Brazil, and is associated with rural and forested areas, where humans may serve as accidental hosts. The southeastern region of Pará state reports the highest number of cases, highlighting its epidemiological significance. Wildlife species, especially carnivores and rodents, play crucial roles as definitive and intermediate hosts, respectively. Although lagochilascariasis can lead to severe clinical manifestations, including chronic soft tissue infections and potential central nervous system involvement, it is likely underdiagnosed due to its similarity to fungal and bacterial diseases. The anthropization of the Amazon Biome, through deforestation and habitat fragmentation, coupled with increased human–wildlife interactions, may be influencing the epidemiology of this parasitosis. This review aims to summarize current knowledge of L. minor transmission routes, the role of wildlife in maintaining its cycle, and the impact of environmental changes on disease patterns. Such insights are vital for One Health strategies, which integrate human, animal, and environmental health approaches to mitigate the disease burden.

9 April 2025 in Preprints.org
Verified
Preprint
Open access
PDF file
FSFernanda dos Anjos Souza
Fernanda dos Anjos Souza
CDCíntia Daudt
Cíntia Daudt
ALANDRE DE MEDEIROS COSTA LINS
ANDRE DE MEDEIROS COSTA LINS
ISIgor Santos
Igor Santos
LTLorena Cáceres Tomaya
Lorena Cáceres Tomaya
FSFlavio Roberto Chaves da Silva
Flavio Roberto Chaves da Silva
Bovine papillomaviruses (BPVs) have been widely characterized from cutaneous warts in cattle worldwide. However, there are still limited studies addressing the geographic distribution of viral types and their potential associations with the histopathological characteristics of lesions, particularly in the vast and ecologically diverse Amazon region. This study aimed to histologically and phylogenetically characterize cutaneous papillomatous lesions in cattle from the Vale do Guaporé, located in the Brazilian Western Amazon. A total of 54 wart samples were collected from 44 cattle clinically diagnosed with cutaneous papillomatosis. Histopathological analysis classified 58.33% of cases as fibropapillomas and 39.58% as squamous papillomas. Molecular analysis, based on L1 gene amplification and sequencing, identified the presence of previously reported BPV types (BPV2, 4, 5, 12, 13, and 15), along with a novel BPV14 subtype and three putative new types (PNT). Statistical analysis revealed that BPV2 was significantly associated with fibropapillomas (p = 0.023), whereas BPV13 was linked to cauliflower-like morphological lesions (p = 0.008). These findings enhance the understanding of BPV diversity circulating in cattle from the Amazon region and provide valuable insights into the clinicopathological aspects of bovine cutaneous papillomatosis, which may aid in future epidemiological surveillance and disease control strategies.